Abstract: Provided are a sucrose synthetase and the use thereof. Compared with SEQ ID NO: 11, an amino acid sequence of the sucrose synthetase contains differences in amino acid residues selected from one or more of the following residue positions: an amino acid at position 36 being V, an amino acid at position 43 being E, an amino acid at position 179 being A, an amino acid at position 395 being R, an amino acid at position 447 being P, an amino acid at position 455 being L, and an amino acid at position 654 being R; and the sucrose synthetase has an activity not lower than that of a sucrose synthetase having an amino acid sequence as shown in SEQ ID NO: 11. By means of catalyzing the synthesis of rebaudioside A, rebaudioside D or rebaudioside M by using a glucosyltransferase and the sucrose synthetase in a combined manner, a cascade reaction is achieved, thereby providing a variety of possibilities for the selection of raw materials.

Abstract: Provided are a digital twinning method and system for a scene flow based on a dynamic trajectory flow, which belong to the field of traffic control. The method includes: extracting and identifying a target semantic trajectory with a detecting and tracking integrated multi-modal fusion and perception enhancement network; extracting road traffic semantics, so as to obtain a highly parameterized virtual road layout top view; obtaining a road layout traffic semantic grid encoding vector based on the virtual road layout top view; constructing a target coupling relation model; constructing a traffic force constraint model; constructing a long short term memory trajectory prediction network; predicting a motion trajectory of a target with the long short term memory trajectory prediction network, so as to obtain the predicted motion trajectory; and obtaining a digital twin of the scene flow based on trajectory extraction, semantic identification and the predicted motion trajectory.